It is important that public-safety responders have a link to communication services (e.g., telephony, data services, and the like) when responding to an incident. However, the reality of the dynamic and mobile nature of the profession is that, in many instances, incidents occur outside the range of the established radio access networks (RANs). To facilitate communication between the responders and offsite utilities, incident area networks (IANs) are often set up using mobile base stations. These mobile base stations establish a link between a given wireless communication device (WCD) (e.g., a handheld mobile radio) and a given network resource, typically using some standard for over-the-air communication, an example of which is 3GPP's Long Term Evolution (LTE), which is one example protocol for a type of wireless communication known as orthogonal frequency division multiplex (OFDM) communication. In addition to mobile radios, some examples of commonly used WCDs include cell phones, smartphones, tablets, notebook computers, laptop computers, and the like. And certainly many other examples of WCDs could be listed as well, as known to those having skill in the relevant art.
It is desirable for public-safety responders to be able to communicate with one another as efficiently as possible for at least the reason that the immediacy and efficacy with which public-safety responders can communicate with one another are quite often determinative of how positive the ultimate outcome of a given incident can be. For the sake of general efficiency and for optimized allocation of network resources, it is important that mobile base stations be coordinated among one another to handle the various connections they facilitate. Accordingly, for this reason and others, there is a need for methods and systems for embedding a supplementary data channel in OFDM-based communication systems.
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The apparatus and method components have been represented where appropriate by conventional symbols in the drawings, showing only those specific details that are pertinent to understanding the embodiments of the present invention so as not to obscure the disclosure with details that will be readily apparent to those of ordinary skill in the art having the benefit of the description herein.